Silicones and siloxanes can be employed for flexibilizing reactive resins. To obtain a chemically stable molded material, those siloxanes which participate in the curing reaction of the reactive resin and are incorporated chemically into the molded material are preferred.
Siloxanes which contain epoxide groups and can be bonded into a molded material in a stable and hydrolysis-resistant manner with the epoxide group via SiC bonds are therefore sought for mixing with epoxy resins.
Epoxysilanes having epoxide groups bonded via SiC are obtained by hydrosilylation of silane hydrides with unsaturated epoxide compounds. Under technologically demanding conditions, with exclusion of water and in an absolute inert gas atmosphere, reaction products can be obtained which must be worked up in expensive purification steps and must be freed from the platinum metal group catalyst required.
Epoxysilanes can also be rendered accessible by epoxidation of unsaturated silane compounds. This is also an involved synthesis which leads to expensive products.
The object of the present invention is therefore to provide a simple process for the preparation of epoxysilanes having epoxide groups bonded via SiC, which leads to a product which is stable to chemicals and heat, has an adequate epoxide content, is compatible with the usual epoxy resins for casting resin applications and can be cured together with these. SUMMARY OF THE INVENTION